FIELD OF THE INVENTION
The present invention relates generally to transcutaneous electrical nerve stimulation (TENS), and more particularly to a device for providing stimulation of superficial sprigs of the Vagal nerve located in the auricle of the ear, and also to a related method of providing such nerve stimulation.
Various afflictions of the central nervous system have caused a great deal of distress to people for all of recorded history. Such conditions include, but are not limited to, emotionally or environmentally induced stress, the presence of long-term pain due to a variety of conditions, muscle tension resulting in general unease, and withdrawal symptoms resulting from addiction to a variety of substances, including nicotine, alcohol, cocaine, opiates, etc. In addition to the more traditional medical therapies such as pharmacological therapy and psychological therapy which have been used to treat these various conditions in people around the world, there exist several less conventional techniques of treating these conditions. Examples of the more unconventional therapies include acupuncture and functional electrical stimulation (FES).
Acupuncture is only recently gaining acceptance in the West, although it has been utilized in China for over 2500 years. Only recently have advances in neuroscience provided a physiological basis for explaining the mechanisms used in acupuncture. Channel phenomena, viscerosomatic relationships, and other mechanisms which bring about beneficial effects are facilitated by the use of acupuncture. The use of acupuncture has long been known to provide medium term relief of pain, and even analgesia for the facilitation of surgery.
For a review of the historical relevance of acupuncture, a two-part article entitled, "A Scientific Model for Acupuncture" may be found in the American Journal of Acupuncture, Vol. 17, No. 3, at pages 251-268 (July-September 1989), and in the American Journal of Acupuncture, Vol. 17, No. 4, at pages 343-360 (1989). This article is hereby incorporated herein by reference.
More recently, various papers have been published which observe that acupuncture may be utilized to provide relief from the symptoms of substance addiction. These findings, which have only been made in the last two decades, have demonstrated that the use of acupuncture may alleviate the symptoms of abstinence syndrome brought on by acute withdrawal from drugs. A high initial success rate has been achieved in detoxification for drugs including nicotine, alcohol, cocaine, marijuana, heroin, methadone, and other opiates. This work is summarized in a paper entitled, "Treatment of Substance Addiction With Acupuncture," which was presented at the Second International Congress on Chinese Medicine in Los Angeles, Calif., in July 1989, which will be published in 1994. This paper is also hereby incorporated herein by reference.
Unfortunately, there are a large number of people who have a fear of needles. While most of these people will tolerate the temporary insertion of a needle in order to inject a drug, they are unwilling to even try acupuncture, except as a last resort. The number of people willing to try acupuncture therapy diminishes even further when they are informed that treatment for addiction involves the insertion of needles into the auricle of the ear, wherein are found superficial sprigs of the Vagus nerve.
Another unconventional therapy, functional electrical stimulation, has been studied for at least several decades, although it is still in its infancy. Electrical excitation of neural tissue has been utilized both to restore missing or impaired body function, and in the treatment of pain. Examples of the former purpose include the operation of artificial prosthetic limbs to replace missing or paralyzed limbs, cochlear stimulation devices to enable an auditory sensation in the deaf, and the provision of visual sensation to the blind.
Unfortunately, the benefits of functional electrical stimulation have been relatively limited in practical application, with the devices being extremely expensive and available only in limited quantities to a small number of individuals. There have also been problems in the development of the technology caused by the polarization of body tissue due to an imbalance in the flow of electrical current through the body tissue.
One of the limited successes in the technology has been in transcutaneous electrical nerve stimulation devices, which administer electrical stimulation through electrodes applied to the skin of the individual being treated. These devices to date have not had efficient output waveforms, or optimized operating procedures. As a result, typical transcutaneous electrical nerve stimulation devices must be applied for several hours at a time, which is counterproductive to the provision of long-term pain relief. This is due to the fact that long-term stimulation can deplete certain central nervous system neurochemicals, with tolerance thereby being established. After this occurs, the transcutaneous electrical nerve stimulation devices are no longer effective.
It is accordingly the primary objective of the present invention that it provide both a device and a related method of operating the device which are capable of efficiently and effectively treating emotionally or environmentally induced stress, promoting endogenous pain control, and assisting in muscle relaxation. It is a further objective of the present invention that it provide both an apparatus and an optimized technique of applying therapy which are useful in the treatment of substance abuse, enabling the withdrawal from use of the substance with substantially minimized withdrawal symptoms. It is yet another objective of device and method of the present invention that they require only a relatively short time for treatment, both in the time required per treatment session, and in the number of treatment sessions required.
Broadly, it is an important objective of the device and the method of the present invention that they be both safe and efficacious in every way. On a more technical matter, it is an objective of the apparatus and method of the present invention that they use a principle of operation which prevents the undesirable polarization of body tissue during operation. It is a further objective of the device and method of the present invention that they not deplete neurochemicals during their operation, and that their operation not result in a tolerance for the treatment being established.
The apparatus of the present invention must be of construction which is both durable and long lasting, and it should also require little or no maintenance to be provided by the operator. In order to enhance the market appeal of the apparatus of the present invention, it should feature both inexpensive construction and inexpensive operation, to thereby afford it the broadest possible market. Finally, it is also an objective that all of the aforesaid advantages and objectives of the present invention be achieved without incurring any substantial relative disadvantage.